Struct NodeInfo 

pub struct NodeInfo {
    pub type_name: String,
    pub id: String,
    pub fields: Vec<Value>,
    pub depth: usize,
    pub parent_id: Option<String>,
    pub parent_type: Option<String>,
    pub line: usize,
    pub child_count: Option<usize>,
}

Information about a parsed node (entity/row).

Represents a single entity parsed from a HEDL matrix row. Contains the entity’s type, ID, field values, and parent relationship information.

Field Access

Fields can be accessed by index using get_field(). The first field (index 0) is always the ID.

Examples

Accessing Fields

use hedl_stream::{StreamingParser, NodeEvent};
use hedl_core::Value;
use std::io::Cursor;

let input = r#"
%VERSION: 1.0
%STRUCT: User: [id, name, email, active]
---
users:@User
  | alice, Alice Smith, alice@example.com, true
"#;

let parser = StreamingParser::new(Cursor::new(input))?;

for event in parser {
    if let Ok(NodeEvent::Node(node)) = event {
        // Access by index
        assert_eq!(node.get_field(0), Some(&Value::String("alice".to_string().into())));
        assert_eq!(node.get_field(1), Some(&Value::String("Alice Smith".to_string().into())));
        assert_eq!(node.get_field(3), Some(&Value::Bool(true)));

        // Or use the id field directly
        assert_eq!(node.id, "alice");
    }
}

Checking Parent Relationships

use hedl_stream::{StreamingParser, NodeEvent};
use std::io::Cursor;

let input = r#"
%VERSION: 1.0
%STRUCT: User: [id, name]
%STRUCT: Order: [id, amount]
%NEST: User > Order
---
users:@User
  | alice, Alice
    | order1, 100.00
"#;

let parser = StreamingParser::new(Cursor::new(input))?;

for event in parser.filter_map(|e| e.ok()) {
    if let NodeEvent::Node(node) = event {
        if node.is_nested() {
            println!("{} is a child of {:?}",
                node.id, node.parent_id.as_ref().unwrap());
        }
    }
}

Fields

type_name: String

The entity type name.

id: String

The entity ID.

fields: Vec<Value>

Field values aligned with schema.

depth: usize

Nesting depth (0 = top-level).

parent_id: Option<String>

Parent node ID (if nested).

parent_type: Option<String>

Parent type name (if nested).

line: usize

Line number in source.

child_count: Option<usize>

Expected child count from |[N] syntax.

Implementations

impl NodeInfo

pub fn new( type_name: String, id: String, fields: Vec<Value>, depth: usize, line: usize, ) -> Self

Create a new node info.

pub fn with_parent(self, parent_type: String, parent_id: String) -> Self

Set parent information.

pub fn with_child_count(self, count: usize) -> Self

Set expected child count from |[N] syntax.

pub fn get_field(&self, index: usize) -> Option<&Value>

Get a field value by column index.

pub fn is_nested(&self) -> bool

Check if this is a nested (child) node.

Trait Implementations

impl Clone for NodeInfo

fn clone(&self) -> NodeInfo

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NodeInfo

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.